JFileChooser 用于生成打开一个文件对话框，也是用于生成“打开文件”、“保存文件”的对话框，

JfileChooser 不依赖本地的GUI 平台，它是纯Java 实现，在不同平台具有完全的行为，并具有相同的

外观风格-JFileChooser used to generate open a file dialog is used to generate the " Open File" , " Save File"　dialog box, JfileChooser GUI does not depend on the local platform, it is a pure Java implementation, the platform has completely different behavior and has the same look and feel